


Gigantic

by BubbleGumLizard



Series: Mystrade NaNoWriMo 2015 [20]
Category: Sherlock (TV)
Genre: M/M, Plot What Plot/Porn Without Plot, Size Kink, Tumblr Prompt
Language: English
Status: Completed
Published: 2015-11-28
Updated: 2015-11-28
Packaged: 2018-05-03 20:39:28
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 2,135
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/5306039
Author URL: https://archiveofourown.org/users/BubbleGumLizard/pseuds/BubbleGumLizard
Summary: <blockquote class="userstuff">
              <p>John seems to avoid Sherlock seeing him naked.  Sherlock wants to fix that.</p>
<p>This is porn.</p>
            </blockquote>





	Gigantic

**Author's Note:**

> Okay, so this is my first PWP. I received a prompt on Tumblr asking for a size kink fic, so I did my best.
> 
> I hope everyone likes it!

“What are you doing?” John demanded, looking at Sherlock, who had entered the room without knocking, as usual.

“I need something,” Sherlock explained, rummaging in the medicine cabinet.

“Sherlock, I’m in the bath!”

Sherlock turned to look at him. He was, indeed, in the bath. “I can see that, John.”

“Good. Then get out!”

“Why? I can’t see anything you wouldn’t want me to see. And anyway. I’ve seen you nearly naked plenty of times.”

“I’m trying to relax. That does not involve you barging in here, trying to see my cock.”

“I’m not trying to see your cock. Though you are awfully protective of it. Why don’t you want me to see it?”

“What? There’s no reason I don’t want you to see it. It’s perfectly normal. What isn’t normal is you being so interested in it. Now go away.”

Sherlock frowned. It definitely seemed like John didn’t want him to see his cock for a reason. He needed to figure out what the reason was. It was vitally important that this didn’t remain a mystery. For purely scientific reasons, obviously.

Sherlock turned and left, leaving what he had gone in there for. How could he see John’s cock? Ah, there was a perfectly easy way. He returned to the kitchen and lit the stove, setting one of John’s jumpers on it. It was a particularly ugly jumper, so no one would miss it. John might, but he’d get over it, eventually.

“John! There’s a fire!” he shouted, standing back and watching the jumper burn.

“What?” John yelled back and Sherlock heard splashing. Good, John would rush out to the kitchen, naked.

When John appeared a moment later, he had a towel wrapped around his waist. He seized his jumped and threw it into the sink, turning the water on to put out the fire and turned off the stove. He turned to Sherlock, an amazed look on his face. “Are you completely mad?” he shouted.

Sherlock shrugged, eying the towel that was in his way. “Perhaps. I didn’t achieve my goal, though. Rather disappointing.”

“And what precisely was your goal?” John asked through gritted teeth.

“This was,” Sherlock said, lunging forward and trying to grab John’s towel and pull it off.

John jumped back, too quick for Sherlock. “Sherlock, leave me alone,” he said in a warning voice.

Sherlock ignored him and tried again. John tripped Sherlock, causing him to fall on the floor, and turned to walk away. Sherlock managed to grab one of John’s ankles and pull him down to the ground, reaching out with his other hand and getting a firm grip on the towel. He yanked it hard and threw it behind him, looking at the now naked John Watson he was holding by the ankle.

“Let go!” John cried, kicking his foot.

Sherlock was too mesmerized to let go. He stared at John’s cock, unable to tear his gaze away.

“What is wrong?” John asked, finally managing to get his foot free of Sherlock’s hand. “It’s just a cock.”

“No, John. There is no conceivable way that could be referred to as ‘just a cock.’ It’s beautiful, John.”

“What?” John was staring at Sherlock now, but Sherlock was still too distracted.

It was beautiful and it was huge. Sherlock had never seen such a large cock, not even in the porn he carefully hid on his computer so John wouldn’t find it. Not even those men, those men who starred in pornography catered to men who liked particularly large penises, could match John in this regard. Not only was it particularly long, but it was so thick as to make it look impossible to fit anywhere. Sherlock stared and licked his lips, imagining what it would taste like and thinking of ways to get to find out.

“Sherlock, stop staring at me.” John’s voice was low, like he was trying to sound annoyed, but under Sherlock’s gaze, his cock was betraying him: it was growing.

Amazed that it could get bigger, Sherlock leaned forward, interested in it. “Why did you hide this from me, John?”

“I didn’t hide anything from you. I just assumed that you wouldn’t have an interest in my cock!”

“How could I not? Can you fuck my mouth?” Sherlock abruptly decided on bluntness as the best course of action. John always liked when he was clear about what he wanted, so he might as well try it.

“What do you want?” John asked, looking confused.

Sherlock stood and helped John up, feeling a little insecure. He was a bit caught up in what he was seeing and may have said too much. “I wondered if you could fuck my mouth. I—I like that.” He looked away, slightly embarrassed.

“Oh god, yes,” John said breathlessly, making Sherlock look at him sharply. He was staring at Sherlock’s mouth and Sherlock could clearly see the effect the thought was having on John. Sherlock smiled and stepped close to John, sliding his hand around the back of John’s head and pulling him in for a kiss.

He had dreamed about doing this for years, but he had never been brave enough to suggest it. Now, however, thanks to his big mouth and John’s even bigger cock, he had thrown caution to the wind and had risked everything. If this was to be the ruin of their relationship, he was going to enjoy it. He wrapped his arms around John and kissed him, pressing their bodies together and moaning as he felt John’s gigantic cock pressing against him.

He slid down to his knees so he was at the same level as John’s cock. He licked his lips once more and then leaned forward and licked the tip of it. John gasped and Sherlock smiled up at him. John was looking down at him, his eyes half-closed. He wanted this as much as Sherlock did. Good.

Sherlock leaned forward and took as much of John’s cock in his mouth as he could. Barely half of it was in before Sherlock’s gag reflex was triggered and he choked, pulling back. Getting hard at the sensation, Sherlock pus his hands on John’s arse and pushed him into Sherlock’s mouth.

He pulled off and looked up at John. “Fuck my mouth,” he said quietly.

“Are you sure?” John asked, looking worried.

Sherlock nodded enthusiastically. “I want to choke on it. Please.”

John put his hands on the back of Sherlock’s head and began thrusting into his mouth, moaning at the sensation. Sherlock kept his mouth open as wide as possible, ignoring the ache that was starting in his jaw.

Soon he couldn’t breathe, choking and gagging on John’s cock. He couldn’t think about anything else: all of his senses were filled with John, overwhelmed by the sensation of John’s huge cock thrusting into his mouth, hitting the back of his throat as Sherlock gagged, moving harder and faster as Sherlock tried to moan around it but was unable to make a sound.

It continued for several minutes. John seemed lost in the sensation, thrusting wildly, moaning and crying out in pleasure. Sherlock was close himself, his mind having shut entirely off except for the giant cock that was currently assaulting his mouth.

As John’s cries reached a fever pitch, Sherlock felt himself come in his pants, his screams of ecstasy were unable to form because of how full his mouth was. He involuntarily tightened his mouth around John, which was just enough to send John over the edge.

He shouted as he came down Sherlock’s throat, giving a few last thrusts before stumbling back.

John sank to his knees in front of Sherlock, reaching out to caress his face. “Are you okay? I got a little carried away.”

Sherlock grinned, feeling dazed. “That was amazing,” he whispered.

John looked pleasantly surprised. “You liked that?”

“Oh, John. That was brilliant.”

“Do you want me to—” John trailed off, gesturing toward Sherlock’s trousers.

“I came,” Sherlock told him, stifling a yawn. “That was unbelievable.”

John grinned and pulled Sherlock to him, kissing him on the lips. “You’re unbelievable.”

“I’m sleepy, John.”

“Of course you are.”

“Come to bed with me?”

“I thought you’d never ask.”

***

When Sherlock woke up, he was fully dressed and next to a completely naked sleeping John Watson. He pulled the blanket back to admire John’s body, looking carefully at John’s flaccid cock, which was still massive.

John shifted and opened his eyes, smiling at Sherlock looking at him. “You have a thing for big cocks, eh?” he asked, stretching.

Sherlock blushed. It seemed so vulgar when it was put like that, but it was the truth. He had always been obsessed with having things in his mouth and when he hit puberty, that obsession turned into wanting huge cocks in his mouth. He had found real men disappointing, however, so he had kept his sexual experience limited to pornography and playing with sex toys.

Until now, that is.

“You’re so big,” Sherlock said, staring down at John’s cock, which was beginning to harden.

“You’re so sexy, Sherlock. Seeing your mouth around my cock was amazing.”

“John?” Sherlock asked, nervous about what he wanted to ask next.

“Yes, Sherlock?”

“Will you fuck me?”

“Fuck you? As in…”

Sherlock blushed furiously. “Will you have penetrative intercourse with me?”

“Of course. Have you ever done anything like that?” John said up, a mix of excitement and concern on my face.

“Not with another person. I have penetrated myself with any number of sexual aids, however.”

John licked his lips at Sherlock’s words. “Sexual aids?” he asked.

Sherlock went to his closet and pulled a box out of a secret compartment in the wall. He put the box on the bed in front of John and opened it, revealing several different types of personal lubricant and five or six dildos of varying sizes, mostly very large ones.

“You’ve used all of these on yourself?” John asked, his voice sounding strained. Sherlock nodded. “Show me,” John commanded.

With a shy smile, Sherlock removed his trousers and pants and picked up one of the bottles of lubricant and poured some on his fingers, slicking them up very well. He repositioned himself so he had access and John had a good view and then he reached behind himself and slipped one finger in.

Used to this sort of penetration, the first finger slid in easily. After working himself with his finger for a moment, he slipped in a second finger and then eventually a third finger. He paused after pulling the three fingers out, looking down at the box and then up at John.

“This is where I normally switch to one of those. But I’d rather have you this time,” he said quietly.

John nodded, his cock standing at attention and looking ready to burst. John quickly slicked it up and positioned himself behind Sherlock, who was on his hands and knees.

“Ready?” he asked.

Sherlock nodded, bracing himself and taking a deep breath as John pushed inside. He had been penetrated countless times, but never by another person and never by anything so big.

“Slowly,” he gasped out and John slid in very slowly, taking a break every inch or so.

Finally, John was completely buried in Sherlock. Sherlock rested his head on his arms panting. He felt like he was being ripped apart. It was painful in the most pleasurable of ways, making Sherlock want to tell John to fuck him as hard as possible. He knew that would be a bad idea, and he instead waited a moment before directing John to pull out and thrust in slowly again.

Eventually they built up a very quick rhythm. Sherlock listened to the sound of their skin slapping together as John fucked him in the arse, feeling with every thrust like he was being split apart by John’s giant cock.

He could feel it more than he had ever been able to feel anything before. Every little movement that John made sent pleasure shooting though Sherlock, making him scream. With every thrust of John’s hips, Sherlock went more and more mad with pleasure, until he was a writhing, quivering mass, capable only of screaming and crying out as John fucked him harder and harder.

Sherlock came suddenly, letting out shrieks that were sure to alarm the neighbors, and felt himself tighten around John, who let out a series of shouts and came as well, filling Sherlock.

John collapsed next to Sherlock, his breathing heavy and irregular. “That was amazing,” John whispered, reaching out and brushing hair off of Sherlock’s face.

“Can we do it again?” Sherlock asked.

John chuckled. “Not right now, love. Sleep now. More sex later.”

“Mm. Good.” Sherlock drifted off to sleep, feeling more satisfied than he ever had before.


End file.
